Source: http://world-of-ru.livejournal.com/2436924.html Basically, if you have a VK3001H in garage by the time the 8.8 patch goes live, it will be transformed into the tier 5 heavy tank (your crew will automatically be retrained), AND you will recieve a VK3002M (new tier 6 medium) for free with a free 100 percent crew, plus one free garage slot. Plus, the removed engines from German vehicles won’t simply disappear, if you have such a vehicle with such an engine that gets removed, the engine itself will be demounted and put in your depot, from where you can sell it or re-use it. Also, allegedly (not 100 percent info): all the changed German vehicles will be put into stock configuration for free, the upgraded modules being transferred to the depot. Which makes selling stock modules very profitable, you’ll get them back for free.

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